Applying Partial Fractions to Solve Laplace Step Function Problems

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step function - laplace...

Homework Statement


y"+y = f(t)

f(t) = 1, t<pi/2
0, pi/2<=t<infinity

The Attempt at a Solution



i now have L{y} = [tex]\frac{1-e^(-(pi/2)s)+s}{s(s^2+1)}[/tex]

but how do i separate them and finish the problem?

thanks
 
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Use partial fractions like always.
[tex]\frac{1}{s(s^2+ 1)}= \frac{A}{s}+ \frac{Bs+ C}{s^2+ 1}[/tex]

Find A, B, and C.
 


HallsofIvy said:
Use partial fractions like always.
[tex]\frac{1}{s(s^2+ 1)}= \frac{A}{s}+ \frac{Bs+ C}{s^2+ 1}[/tex]

Find A, B, and C.

so no i have f(t) = 1-cos(t)+sin(t) - L{[tex]\frac{e^(pi*t/2)}{s(s^2+1)}[/tex]}

how do i get the last laplace?
 
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